In our second annual ranking, Business 2.0 has compiled an unabashedly subjective list of people, products, trends, and ideas that are transforming the world of business.

Why he matters: Kevin Rose may be the camera-ready face of news aggregator Digg and online video network Revision3, but Adelson is the quiet guy in the background who builds them into successful businesses.

Rose fronted the initial cash for Digg, but Adelson is widely credited with using his business savvy to transform Rose's brainchild into an influential new way to compile the news. Adelson also runs the show at Revision3, which is racing to create TV-style online video programs. Without Adelson, the people-powered content revolution wouldn't be quite so powerful.